Method and apparatus for removing excess galvanizing metal from conduit or the like



2,606,846 5 GALVANIZING Aug. 12, 1952 w. s. PEARSON METHOD AND APPARATUS FOR REMOVING EXCES METAL FROM CONDUIT OR THE LIKE 5 Sheets-Sheet 1 Filed May 21, 1948 Aug. 12, 1952 w. 5 PEARSON 2,606,846

METHOD AND APPARATUS FOR REMOVING EXCESS GALVANIZING 5 Sheets-Sheet 2 METAL FROM CONDUIT OR THE LIKE Filed May 21, 1948 Aug. 12, 1952 w. s. PEARSON 2,606,846

METHOD AND APPARATUS FOR REMOVING EXCESS GALVANIZING METAL FROM CONDUIT OR THE LIKE 5 Sheets-Sheet 3 Filed May 21, 1948 Aug. 12, 1952 w. s. PEARSON 2,606,846

' METHOD AND APPARATUS FOR REMOVING EXCESS GALVANIZING METAL FROM CONDUIT OR THE LIKE Filed May 21, 1948 5 Sheets-Sheet 4 Ill Aug. 12, 1952 w 5 PEARSON 2,606,846

' METHOD AND APPARATUS FOR REMOVING EXCESS GALVANIZING METAL FROM CONDUIT OR THE LIKE Filed May 21, 1948 5 Sheets-Sheet 5 Ii Wilizizw 1711 94750 \l i at ented Aug. 12,

UNITED STATES PATENT OFFICE :7

METHOD AND APPARATUS FOR REMOVING EXCESS GALVANIZING METAL FROM coN nm'r on rm: LIKE William S. Pearson, Baltimore, Md., assignor to Clifton Conduit Company, Inc., Baltimore, Md., a corporation of Maryland 14 Claims.

This invention relates to improvements in the removal of excess galvanizing metal from freshly galvanized pipe or conduit and more particularly concerns the removal of the excess galvanizing metal While the same is in a fluid condition.

In the galvanizing of pipe such, for example, as is used as conduit for electric wiring, the entire pipe section is immersed in the galvanizing metal comprising molten zinc. The end result desired is a uniform coating of the zinc on the pipe and any excess molten galvanizing metal that remains on the pipe after it has been removed from the galvanizing bath must be removed if stalactiform and lumpy adherences of the excess metal are to be avoided on the exterior of the tube or passage-blocking accumulations on the interior of the tube after cooling and solidification of the metal.

It is therefore an object of the present invention to provide an improved method of and apparatus for removing the excess galvanizing metal from conduit tubing or the like efiiciently, rapidly, and safely.

Another object of the invention is to provide an improved method of and apparatus for removing excess galvanizing material from tubular articles operative in conjunction with a conveyor assembly for transporting the articles from the galvanizing tank to a receiving point.

A further object of the invention is to provide an improved system for removing excess galvanizing metal from sections of freshly galvanized conduit and in which means for removing the excess galvanizingmetal are controlled in operation by the successive sectionsof conduit to be treated.

Still another object of the invention is to provide an apparatus for removing excess galvaniz ing metal from freshly galvanized conduit and including a plurality of interrelated components automatically operable in timed sequence under th control of each individual section of conduit to be treated and following a predetermined path of movement.

Yet another object of the invention is to provide in an improved apparatus for removing excess galvanizing metal from sections of conduit, novel safety means for avoiding danger'of injury to adjacent workers from splatter of the excess molten metal incident to its removal from the conduit.

A still further object of the invention is to provide an improved control system for apparatus by which excess galvanizing metal is removed from freshly galvanized tubular articles.

It is another object of the invention to provide improved high pressure blow-out means for removing excess galvanizing metal from the interior of freshly galvanized tubular articles.

Other objects, features and advantages of the present invention will be readily apparent from plan view taken substantially on the line III-III.

of Fig. 1; I

Figure 4 is a fragmentary vertical sectional view taken substantially on the line IV-IV of Fig. 1;

Figure 5 is an enlarged fragmentary sectional plan view of the excess galvanizing metal remov ing portion of the apparatus disclosing the relationship of parts. atthe instant of blow out of a conduit section;

Figure 6 is a vertical sectional View taken substantially on the line VIVI of Fig. 1;

Figure 7 is an enlarged vertical sectional view taken substantially on the line VII-VII of Fig. 1;

Figure 8 is an enlarged fragmentary elevational view, partially in section, of the pinch feed roll drive arrangement viewed from the opposite side of that shown in Fig. 1;

Figure 9 is a fragmentary sectional elevational' view of a modified form of safety valve'means that may be used in the invention;

Figure 10 is a vertical sectional view taken substantially on line XX of Fig. 9; and

Figure 11 is a schematic view including an electrical diagram for automatic operation of the apparatus.

According to the present invention, excess molten galvanizing material is blown from the interior of a freshly galvanized tubular article. and the spatter of excess metal ejected from the tube is confined within a safety chamber. Superheated steam has been found to be an excellent blowing medium. Other heated gaseous medium, such as air or other gas may be used if desired.

The exterior of the tube is freed from excess galvanizing metal by subjecting the same to the action of a fluid swab which may comprise jets of superheated steam directed to converge circu apparatus of the present I 3 larly about the tube while the tube is run through the fluid swab. By preference the external swab is so located that the excess galvanizing metal removed from the tube thereby is received in the aforesaid safety chamber.

The internal fluid swabbing or blow-out and the external swabbing steps of the present method of removing excess galvanizing metal from the tubular article are so related in practic that excess galvanizing metal ejected from the interior of the tube cannot whip around to the exterior of the tube about the exit orifice or cling to the tube extremity.

The excess galvanizing material removal process is carried out in a practical, efiicient manner on successive freshly galvanized tubular articles in a timed cyclical sequence controlled by each of the successive tubular articles.

Moreover, removal of excess galvanizing material from the freshly galvanized tubular articles is eifected coincident with transportation of the articles from the galvanizing bath from which they have been removed to a delivery or receival point. a

When a tubular article such as a conduit E5 of the type which is commonly employed for housing electrical wires in building structures and the like, is removed from a galvanizing bath which may be contained in a tank 18 (Fig. 1) it is, of course, very hot. Excess galvanizing metal must be removed from the duct while it is still above the melting point of the galvanizing metal. Accordingly, it is highly desirable to handle the freshly galvanized sections of conduit l5 mechanically from both efiiciency and safety standpoints.

For handling the freshly galvanized sections of duct 15, novel apparatus is provided including a magnetic conveyor comprising a pair of successively operable overhead conveyor rolls ii and ill, a second pair of successively operable overhead conveyor rolls is and 2c spaced in advance of the first mentioned pair of rolls, and a cooperating pair of pinch feed rolls 2! located in the space between the pairs of magnetic conveyor rolls. Support for the conveyor and feed rolls is provided by a supporting framework 22 including spaced parallel top rails 23 and 2 disposed at an oblique angle upwardly. The shafts for the respective overhead conveyor rolls are journalled in bearing assemblies 25 secured to and carried by the frame rails 23 and as.

All of the overhead conveyor rolls ll, l8, l9 and Zfl'are driven from a common source of motive power such as an electric motor 21 which may be supported upon a motor bracket 28 on top of a housing 29 disposed intermediate the companion pairs of conveyor rolls. Drive sprockets 33 on the motor shaft have respective sprocket chains. 3i and 32 trained thereover, the sprocket chain 3| being further trained over a driven sprocket 33 On the shaft of the roll I7 and the chain 32 being further trained over a driven sprocket as carried by the shaft of the roll 19. Sprockets 35 on the shafts of the rolls H and 18 have a sprocket chain 3? trainedthereover so that these rolls are driven in unison. lhe shafts of the rolls l9 and 26 have respective sprockets 38 thereon over which is trained a sprocket chain 39 by which these rolls are driven in unison. It may be observed at this point that the various sprocketsare of such correlated diameters that all of the conveyor rolls ll, l8, l9 and 20 are driven at the same surface speed so as to avoid any scufiing of the freshly galvanized surfaces of the conduits. The speed of travel is also fast enough to avoid any area chilling of the conduits or overheating of the rolls.

The pinch feed rolls 2! are mounted adjacent to the side of the housing 29 nearest the conveyor rolls l9 and 2B. The shafts for the rolls 2| are supported by appropriate bearings ill (Figs. 3 and i) carried by brackets ll supported by the frame 22. For adjustment of the bearings or journals 43 to. vary the spacing between the pinch feed rolls 2i and also to effect proper adjustment thereof with respect to the path of movement of the conduit sections i5, suitable adjusting screws i'z'may be provided.

Means for driving the pinch feed rolls 2! at the same surface speed as the magnetic conveyor rolls is provided in the form of a sprocket chain 53 (Figs. 1, 2, 4 and 8) trained serpentine fashion over sprockets id on the respective shafts of the feed rolls, over an idler sprocket above the upper of the roll shaft sprockets, and over a drive sprocket ll on a drive shaft 48. Bearings 49 support the shaft i8 upon the frame rails 23 and 2 3, and the shaft has a sprocket 50 thereon which is in driving mesh with the roll driving motor actuated sprocket chain 32.

By preference the drive sprocket 31 is rotatably bearinged on the shaft i8 and is operatively coupled with the shaft by means of a slip clutch 5! so that in the face of resistance to rotation of the sprocket il, it can lag behind the shaft 48.

For purposes which will presently appear, means are preferably provided for heating the pinch feed rolls 2%. Such means may comprise any of a number of expedients such as flame heating, steam or water heating, but a desirable device comprises electrical resistance heating by means of a controlled electrical resistance heating circuit 22-5 (Fig. 4), including resistance elements 2!?) in the rolls 2 l. Thus, the rolls 2| are properly heated while in use but not excessively.

All of the conveyor rolls I2, H3, H3 and 2B, and the feed rolls ii are of arcuately annularly grooved periphery with the nights thereof aligned to accommodate each of the conduits 15 in a substantially straight longitudinal path.

In practice, the lower end of the overheat conveyor system is located adjacent to the galvanizing bath, vat or tank l8 and the successive hot duct sections 55 removed from the galvanizing bath are delivered to the magnetic conveyor rolls l7 and I8 to the lower sides of which the ferrous duct sections will adhere and find a centered position as a result of the magnetism of the conveyor rolls. Since the rolls I! and is are driven to move the supported duct section onwardly and upwardly, the leading end of the duct will find its way between the pinch feed rolls 2!, the spacing of the latter feed rolls being slightly less from the first conveyor roll ll than the length of the conduit section i5. By having the first conveyor roll E8 of the final pair of conveyor rolls spaced a shorter distance from the conveyor roll (8 than the len th of conduit l5, the advancing conduit section is engaged under the conveyor roll i9 before it leaves the conveyor roll I8 and thus continues undeviatingly in its path, rapidly advancing from the conveyor roll l9 to the conveyor roll 23.

After the trailing end of the conduit section i5 leaves the feed rolls 2i, it is allowed to drop down onto a take-away conveyor below the conveyor rolls i9 and 28. In a preferred form the latter conveyor comprises a [pair of spaced parallel conveyor chains 52 and 53 (Figs. 1, 5 and 6). The conveyor chains may be of the sprocket type supported by sprockets 54 carried by brackets 55 attached to the frame rail 24 at the end of the chain conveyor nearest the magnetic roll conveyor, while suitably supported sprockets 5I carry the opposite end of the chain conveyor and intermediate supporting sprockets 58 afford sag preventing support. As best seen in Fig. 6 the portion of the conveyor chains 52 nearest the overhead conveyor is depressed in conformity with the oblique angle of the overhead conveyor, but the tilted angle thus existing in the chain conveyor is safely within the angle of repose of the conduits dropped onto the chain conveyors so that the conduits will not slip therefrom.

The housing 29 may be made from sheet metal in the form of an upright cabinet extending from well below the magnetic conveyor such as from the floor of the room in which the apparatus is located to well above the conveyor, substantially as shown in Fig. 1. The back of the cabinet may be secured to the frame rail 23, while the remaining frame rail 24 may be interrupted to accommodate the cabinet as best seen in Fig. 2. The housing or cabinet 29 provides a complete enclosure and may have a door 59 by which it can be opened for access to the interior as desired. For passage through the housing 29 of the successive sections of conduit, the side walls of the housing are provided with respective apertures 60 and GI adjacent to the conveyor. roll I8 and the feed rolls 2|, respectively, and aligned with the diagonal path of movement of the duct sections.

The main purpose of the housing or cabinet 29 is to provide a safety chamber to receive spatter of excess galvanizing metal blown from the newly galvanized conduit sections I 5.

Means for removing excess galvanizing metal from the exterior of the conduit sections I5 comprises a fluid swab device 62 in the form of a tubular ring of slightly larger diameter than the outside diameter of the conduit section I5 and disposed concentric with the passage opening 6| in the wall of thehousing 29. The swab 62 receives suitable heated fluid such as superheated steam from an appropriate source by way of a duct 63 and has an annular series of jet ports 64 (Figs. 3 and 5) directed on convergent axes into the opening 6| generally opposite to the direction of movement of the conduit sections I5 through the swab ring. The fluid jets from the ports 64 impinge upon the exterior of the conduit I5 in an annular area just inside the adjacent wall of the housing 29, and thus excess molten galvanizing material swabbed from the conduit is received within the housing and all danger of spattering of the excess galvanizing metal is avoided. The swab 62 may operate continuously or it may be operated intermittently as each of the conduit sections [5 enters and remains within the eifective range thereof.

For cleaning the interior of the-conduit sec: tions I5 of excess galvanizing metal, means are provided for blowing a blast of fluid through the interior of the conduit while the trailing end of the conduit is still within the housing 29. To this end, there is provided a generally gooseneck blow tube 65 (Figs '1, 5 and 7) having a bellmouth 61 which, as shown in dash line in Fig. 1 and full line in Fig. 5 is adapted to receive'the forward extremity of the freshly galvanized conduit I5 to be cleaned for blowing a blast of fluid through the conduit, such fluid preferably comprising a heated gaseous medium such as superheated steam.

Since it is necessary not only to clear the end of the cleaned conduit section I 5 from" the mouth of the blow tube, but also for the conduit I5 to move a further distance forward to clear the trailing end thereof from the housing 29 and the feedrolls 2|, it is desirable to have the blow tube 65 movably mounted with respect to the point at which it engages the forward extremity of the conduit when introducing a'cleaning fluid blast into the conduit. To this end, the blowv tube 65 is mounted pivotally upon a suitable support which in the present instance comprises a steam pipe 68 carried by a bracket 69 on a frame member I0 preferably comprising an upright metal angle bar. The journal for the blow tube preferably comprises a horizontal sleeve member 1| threaded into a T-fitting I2 on the lower extremity of the blow tube. A plug I3 in the lower end of the T-fitting carries a thermal element I4 in spaced relation opposite the mouth of the steam pipe 68.

The pivotal mounting of the blow tube65 is such that the blow tube can be rocked into and out of conduit-blowing position. Means for effecting this rocking of the blow tube may comprise a steam cylinderl5 carried pivotally-by a bracket 11 on the frame 22 and having a :reciprocable piston rod I8 pivotally connected at its outer end to the blow tube.

Clean-out fluid need issue from the blow tube 65 only substantially while the blow tube is in operative association with one of the conduit sections I5 to be cleaned. Accordingly, means.

are provided for admitting blow-out fluid to the blow tube as required, such means herein comprising a gate valve assembly I9 having a relatively elongated operating stem controlled by a piston type steam operator 8|. The stem 80 is surrounded throughout the major portion of its length by a finned radiator sleeve 82 for dissipating heat of the superheated steam transmitted from the gate valve to the stem. An appropriate shut off valve 83 may also be interposed in the steam pipe 68 and preferably ahead of the gate valve I9.

Inasmuch as the conduit clean out blast from the blow tube 65 drives through the conduit with great force, as is desirable to effect a thorough clean out of excess molten galvanizing metal, the excess metal leaves the trailing terminal port of the conduit at high velocity, and would, if un: controlled spatter over a considerable area and to a substantial distance. However, since the trailing end of the conduit is within the housing 29 this spattering is controlled. However, since the conduit entry opening 60 is directly in the line of fire of the ejected excess galvanizing metal, it is highly desirable to provide means for blocking the ejecta from reaching the entry opening. Herein such means comprises a valve or bafile member 84. In a desirable form the baffle member 84 comprises a flexible steel plate anchored at one margin to the back wall of the housing cabinet 29 and adjacent to the exit opening BI as by means of a clamping bar 85 and bolts or screws 81. The remainder of the baliie plate 84 remains unfastened so that the plate can be flexed into intercepting relation in front of the entry opening 60 after a galvanized conduit l5 has passed through the housing and the trailing end clears the path of movement of the flexible bafile, and the baffle can promptly be swung back out of the path of a succeeding conduit section following the ejectment of excess galvanizing metal from the preceding section.

Means for flexing the bafile plate 84 into and out of ejecta intercepting relation comprises an 7. angular-swing rod 88 pivotallyconnected'ton-the free end'margin'of the plate 84 a-siby having such free'margin curled about the rod, while the remainder of the rod projects upwardly and generally forwardly and has a coupling head 83 fixedly secured toan actuating shaft 93 journalledat-its'lower end in a bearingbracketsl and projecting upwardlythrough the roof of the housing'29 The upper end of the shaftlfill has attached thereto a crank arm em (Figs/1 and 2) the free end of which is pivotally connected to a piston rod 92 of a steam operated piston and cylinder assembly 93 pivotally carried upon the roof of thehousing 29.

An important advantage accruing as theresult of using a'fiexible plate for the bafile member'84 resides in theself-cleaning properties of such plate as it is flexed back and forth. That is, the molten zinc spattered thereagainst as ejected from the successive conduits I5 solidifies thereon and as itaccumulates in patches'is from time to time flexed oil in flakes and lenticular masses and drops to the floor "of the cabinet. This avoidsthe bafiie member 85 becoming overweighted with the surplus zinc and also maintains it'iree for-efjcient flexing into and out of bathing position.

In order to operate the apparatus efficiently at high speed, means are provided for cyclic functioning-of theblow tube 65 and the baffle member a 84 controlled by the successive conduit sections I5 to be treated. Herein this isaccomplished electrically substantially as shown schematically in Fig. 11. -Each of the magnetic conveyor rolls I1, I8, I9 and "23 has associated therewith an electromagnet coil structure 85, which is also shown in Fig. Z-as carriedbythe respective'shaft for each of the conveyor rolls. Electrical energy for the electromagnet structures is derived from a direct current source such as a power line 81,

the electromagnets for the coils ll and it being supplied through leads 9% controlled by a master switch 99, while the electromagnet structures for the rolls I9 and 29 are supplied through leads I023 contro'lledby a master switch I-Qi.

As shov'In-in'Fig. l1,the entire systeln'is in an inactive st'ate. Prolnptlyupon closing of the switch 99 magnetizing of the conveyor rolls H and I8 occurs and continuesuntil the switch is again opened at the end of a period of continuous operation. Att-he same time the switch ill: will be closed; out magnetization of the conveyor rolls l8 and 26 will not occur until a relay type switch I 82 which interrupts the- -circuit pro vided by the leads idols-closed. The switch iill-isautomati- (rally-controllable in order to render magnetization-of the rolls i9 .and 2!! selective.

The energizing circuit for the drive motor 2"! has not been shown-in Figl 'llsince such circuit is independentof the electrical controlcircuits shown in the control diagram. Hence it will be presumed that at the same time or prior toopening of the switches'fifi and Ill! the control switch (not shown) for the 'drive motor 21 can also be closedto energize the motor and start the conveyorrcll and feed roll 'drive into operation.

A cycle of operation involving the cleaning of excess galvanizing metal from one of the conduit sections I 5 will now 'be described. Promptly upon feeding one of thefreshly galvanized 'ccn cluit sections l5 to the undersides of the conveyor rolls H and I8, which have nowfbeen placedin rotary as well as magnetic operation, the rolls, by their magnetic attraction hold the conduitsection to them and cause itto assume a centered relation in the bi'ght of the rolls, while at the same time initiating advance of the magnetically supported conduit section onward toward the feed rolls 2!. The leading extremity of the conduit section i5 passes through the entry opening 60 in the spatter housing 29 and while still carried by both of the conveyor rolls It and I8 passes on through the exit opening 6i and enters between the pinch feed rolls 2 I.

Promptly upon engagement of the conduit section by and between the conveyor rolls I"! and 58, a low voltage electrical circuit is completedby way of a transformer it, which may be of eight to ten volt capacity, for example, an electrical lead IN, a relay type switch I65, an electrical lead Iil'l, the shaft of the conveyor roll I8, through the conveyor roll and the duct section to the conveyor roll I! and its shaft to ground by way of aground connection I08. This opens the normally closed relay switch H35 and affords a gap in an electrical circuit including a power lead I09 and-a branch electrical lead I I0. Since the feed rolls 2i are grounded as indicated at I I I the relay switch energizing circuit completed by the advancing conduit section will remain closed even after the trailin end portion of the conduit leaves the conveyor roll ll.

At the beginning of operation aswitch H2 is also closed and this completes a circuit through a power lead IIS, an electrical conductor H4, a closed flexible switch arm IE5 and a power lead H1 through which the relay switch 152 is energizedand closed to complete the magnetizing circuit through the leads I for the conveyor rolls i8 and 21!. Hence, as the conduit section I5 to be cleaned advances successively to the conveyor rolls l9 and 23 it is engaged and sustained thereby.

Upon engagement of the conveyor roll I9 by the advancing conduit section I5, an energizing circuit is closed from the transformer 183 through the lead lo l, a branch lead H8, the shaft of the roll is and the roll Hi, the conduit i5 and the grounded feed roll FBI to energize a relay type switch H9 for closing a switch gap I28 in the electrical lead Hil. When the trailing end portion of the conduit I5 leaves the conveyor roll I8, the energizing circuit for the relay switch IE5 is broken, and this switch returns to closed condition, thus closing a circuit by way of the lead I I9, and a power lead IZI to energize a solenoid I22 to release a stop bar 423 from the stop lobe of a one lobe control cam lid carried by a cam shaft Means are provided tending normally to rotate the cam shaft I25 clockwise as viewed in Fig. 11 and comprising a continuously running motor l2? which may be connected with the alternating current power line through power leads I23 controlled by a master siwtch I29 which is closed at the start of operation of the apparatus. The motor shaft carries a worm I39 which drives a worm wheel I3I relatively rotatably carried by the shaft 425 and having operative connection with the cam shaft by way of a slip clutch I32. Thus, when the stop arm or bar I23 is in stopping relation to the cam I24, the cam shaft I25 is held against rotation while the worm wheel l3! continues to rotate. However instantaneously upon release of the stop bar I23 by energization of the solenoid I22, the cam shaft I25 is set into rotarymotion by way of the slip clutch I32.

Rotation of the cam shaft sets into motion a series of progressively acting switch cams which control operation of the blow tube 65. A one lobe first cam I33 which at the start of rotationof the cam shaft I25 holds a flexible contact switch arm I34 on the conductor II4 open advances until the flexible contact snaps past the lobe of the cam and closes the switch to complete an electrical circuit by way of a lead I35 and a power lead I31 to energize a double acting solenoid operator I38 to actuate and open a steam valve I39 which controls operation of the cylinder and piston actuator 8I to open the gate valve I9 and pass a charge of superheated steam to the blow tube 65. Closely following this the cam I33 opens the switch I34 and a second one lobe cam I49 releases the flexible contact arm of a switch I4I toclose a circuit by way of the conductor H4 and an electrical lead I42 and the power lead I31 to operate the solenoid I38 in opposite direction to reverse the steam valve I39 and thereby reverse the steam piston actuator 9| and close the gate valve I9.

The blow tube 65 is initially in position to receive the leading end of the advancing conduit section I5 within the bell mouth 61, as shown in full outline in Fig. 11, just before the trailing end leaves the spatter chamber 29. This means that further advance of the conduit section is halted and the feed rolls 2I stalled as permitted by the slip clutch 5I. However, the conveyor rolls I9 and 2| continue to operate and it is, therefore, desirable to release the conduit section therefrom to avoid chilling of the conduit or scuffing its external galvanizing coat. Accordingly, just as the leading end of the conduit enters the blow tube mouth 97, the conveyor rolls I9 and 2| are demagnetized by opening of'the switch I92 to break the magnetizing circuit I90, a cam I58 on the shaft I acting at the proper time to open the switch H5 which controls the switch I92 through the circuit III. This permits the conduit section to drop away slightly from the conveyor rolls I9 and 29 from the broken line position of Fig. 11 to the dot-dash position. At this point the conduit section is supported by and between the feed rolls 2I and the blow tube 95, the stalled feeding pressure of the feed rolls holding the leading end of the conduit firmly in the blow tube mouth 67.

Timing of the conduit blow-out delivery of a charge of superheated steam to the blow tube 65, as well as the length of the blow tube are so calculated and coordinated that the expanding charge of superheated steam reaches the blow tube mouth 65 an instant before full contact is made between the leading end of the conduit section I5 and the base of the inside of the bell mouth 61. This assures that all air will have been purged from the blow tube 65 prior to projection of the charge of superheated steam into the conduit section I5, and thus utmost excess metal cleaning efliciency of the superheated steam is attained within the bore of the conduit section I5, with respect to both the heat and velocity of the steam. Since the blow tube 65 engages the conduit section I5 just before the trailing end of the conduit gets to the exit port 6| in the spatter cabinet 29 and holds the conduit against further advancing movement for the relatively brief interval required for the shot of superheated steam to traverse the length of the conduit and blow the conduit clear of excess galvanizing metal, all of the excess material swabbed from the conduit is received within the cabinet.

Immediately following the blow-out action, a single lobe cam I43 releases the flexible contact arm of a switch I44 to close a circuit from the conductor II 4 through a lead I45, and a branch lead I41 from the power lead I31 to actuate a double acting solenoid operator I48 to'turn a steam valve I49 and actuate the piston of the blow tube swing actuator I5 to swing the blow tube 65 out of engagementwith the leading end of the conduit section I5. This releases the conduit section for further advance by the feed rolls 2I to clear from the cabinet '29 and the feed rolls and then dropirom' the feed rolls and theblow tube mouth to the take-away conveyor 52-1-53.

Then a succeeding one lobe cam I59 on the cam shaft I25 comes rotativelyto .the pointwhere it releases a resilient contactarm of a switch 'I5I to close a circuit from theconductor I I4 through an electrical lead. I52 andthrough the opposite side of the solenoid operator I48and. the branch lead I41 and the power lead I31 to energize the solenoid for reversing'the" steam-valve I49iiand thus reversing the blow tube operator I5 toswing the blow tube 65 back to the blow-Out position for receiving the leading end ofthe next succeeding conduit section I5. V x

.While the blow tube 65 has been operated-as described, the deflector plate 84 has also been' actuated. Tothis end, when the switch I closed as an incident to breaking of the circuit including lead I 91, a circuit is closed including the lead I99, the lead branch II9,'a lead I53, and a power lead I54 to energize a two-way solenoid operator I55 which turns a steam valve I5'I to efiect-actuation of the operator 93 for swinging the crank arm 9I This works the shaft 99 to swing rod 88 for flexing the baifie 84 into safety closing'position relative to the entrance opening 60 in the spatter chamber 29. e That is, -the deflector is swung from the dot-dash position shown in Fig. 3 to the full line position. In view of the relatively high speed with which the conveyor and feed rolls operate, the trailing end of the conduit I5 is rapidly cleared from the path ofmovement of the deflector 84 ahead of deflectional swinging thereof. Thus the deflector 84 is swung into the safety position just ahead of or coincident'with the blow-out action of the blow tube 65. I

The deflector 84 is swung back out of the path of the next succeeding'conduit section I5 by the closing of a circuit through a branch lead I69, the power lead I99'and thepower lead. I54 for energizing the solenoid operator I55 in the opposite direction to reverse the steam valve I51. This occurs when the switch II9-reverses as an incident to dropping of the preceding conduit section from the conveyor roll I9 and opening of the relay energizing circuit including the lead II8. e

The cam I58 travels onto the, point where. its lobe releases the resilient contact element. of the switch II5,'so that this switch closesand effects reenergization of the relay switch I92 to again close the magnetizingcircuit for the rolls I9 and 29 whereby to recondition the latter for the next operation. At this same time-therholding cam I24 is engaged by the stop arm I 23 which in the meantime has dropped back onto the cam I24 by deenergization of the solenoid operator I22 as an incident to opening of its-energizing circuit by shifting of the double; acting relay switch H9. 'The'control system-is now ready for another cycle of operation'as' initiated and controlled by 'a succeeding one of the conduit sections I5 to be cleaned. l

It will'be understood, of course, that the several control cams I33, I49, I43 and I59, are so contoured and adjusted with respect to one another that opening and closing'of the respective switches controlled thereby occurs l in" proper 11 timedsequence; Itwill also be understood; that all of the; several .operationsrdescribed; occur in relatively; rapid sequence'coordinated. with the fairlyrapid movementiimparted to the conduit sections l by the. conveyor:rolls and pinch .feed rolls;

If desired; a swinging type of splatter deflector I61 .may be utilizedasrshown-inthemodified form of Figs. 9; and 10; To this. end, the deflector 'as-shown iniullline. in Fig; 9 relative to theconduittentry openingfiil' to the. dot :dashrdefiecting, safety positionshown to block the: entry opening at the time a conduit section" is beingv blown. Actuation of the deflector or baffle Isl may be 'efiected' in the same manner as previously described in oonnectionwith the flexible deflector 84. In this modified 'form, furthermore, the es:- ter-ionof the conduitlfi isadapted to be cleaned by-a ring type fluid swab e2 disposed adjacent. to the exit opening 61', the same as'd'escribed in connection with the ring swab 62;

Itwill, of course, be understood that various details of construction may be variedthrough a -wide-range without departing from the principles of this-invention and it is, therefore, not thepurpose-to limit the patent-granted'hereon otherwise than necessitated by the scope ofthe appended claims:

rclaim as my invention:

1'. In-combination in apparatus forcleaning excess'galvanizi-ng metal from freshly galvanized conduit sections; an overhead'conveyor comprising-"a seriesof grooved magnetic conveyorrolis, a blow -tube operable when the conduit sections have respectively reached a certain position upon the conveyor to engage theleadingend ofwthe conduit section and blow a' swabbingblast through the interior of the section; and means including-'an-electrical system controlledby the successive conduit sections inassociation with said-conveyor rolls for actuating said;- blow tube.

2. In combinationin apparatus of the' characterdescribed, a cabinet having-an entryopening and an exit; opening, means for moving-a freshly galvanizedarticle into the entry opening and through the cabinet out-of theexitopening, means .exteriorly of the exit opening for swabbing the conduit-by-fiuid pressure directed into i the exitopening so. that-spatter of' excess galvanizingmetal from the article is received within the chamber of 1 the cabinet, means within the cabinet movableginto position after the trailing endof' the article haspassed the entry opening for blocking escape of spattered excess galvanizing metal through said entry opening, and means automatically activated by the excessivearticles for-moving said spatter blocking means into and out of-the spatter blocking position.

3. Incombination in apparatus: of'the character described, a cabinet having an entry'opening and an exitmpening; means for moving a freshly galvanizedtarticle:into-the entry; opening and through the cabinet out ofthe exit opening, means exteriorly of the, exit openingifonswabbing the conduit by fluid pressure directed into the .exitopeningso that. spatter of excess galvanizing metal fromthe article is-received. within the-chamber of the cabinet,andv means. within thercabinet movable into position after thetrailing end of the article has passed the entry openingifor blocking escape of spattered excessgalvanizingg metal through said entry opening, said spatterrblocking means comprising a flexible plate, securedgfixedly along one edge thereof at the interionofthe chamber, and means for flexing the: plateinto the splatterrblocking position.

4. Incombination in apparatus of thecharam ter'described', a .cabinethaving an entry opening and: an:exitopening; means for-moving a freshly galvanizediarticle into: the entry opening and through-.the; cabinet out of the exit opening, meansextericrly of-the .exit opening for swabbing thee conduit by iiuidpressure: directed into the exitopening sothat spatter; of excess galvanizing metal from-the article is received: within; the chamber of the cabinet, and means-within the cabinetimoyable intoposition after the trailing endof the article has passed the entry opening for: blocking. escapetoi spattered excess galvanizeing, metal through said entry'opening, said; spatter-blocking meanscomprising abaiilezplate movable. inits plane into. and outoispatter-blocking position.

5. Inpcombination. in apparatus for removing excessgalvanizing metal from. freshly galvanized conduit sections, a' series of overhead magnetic conveyor rolls, a. pinchfeed roll set at anintermediate point in and coordinated in operation withthe set of magnetic. conveyorrolls, means fordriving theconveyor rolls andisaid pinch feed rolls, a spatter cabinet structure interposed be.- tween the;pinch feedrollsand' the adiacent' conveyor" roll in thetrailingi direction. of the. conveyor. system,. conduit. blow-out means operative atthegiorward endoi theiconveyor system, electrical means afiordingconveyor roll magnetizing circuits and cyclically operable :circuits'controlled by eachsuccessive conduit section handled by the conveyor system for'op'erating said blow-out meanszandl for effecting sequential deenergization ofjthe leading. conveyor ro-ll'sfollowing said pinch feed rolls tov drop the. conduit sections to make way for succeeding conduit sections, said spatter cabinet structure having a spatter defiector. therein movable into position between successive conduit sections to receive excess galvanizing metal blown from each section and operable through the medium of appropriate electrical circuits in said electrical means.

6. In apparatus for removing excess molten galvanizing 'metal'irom conduit sections, a movable blow tube having a' generally bell-mouth, means comprising a conveyor for moving the successive conduit sections to drive the leading ends of the sections into blow-out relation within said tube mouth, means fondeliveringashot of heated swabbing fiuid to the blow tube as required, means for moving the tube out of the way' of each blown conduit section to permit it'to clear away to be replacedby a succeeding section. to be blown, and means actuated by-the conduitsections for controlling. the operation of said fiuiddeliveringmeans and said blow tube moving means.

'7. In a method of removing. excess-molten galvanizing metalfrom tubular freshly internally and" externally galvanized'articles, the steps of blowing the excess molten galvanizing material from the external surface. of the article progressivelyv from. one end to the opposite endof the article, andwhile uninterruptedly continuing the external blowing-at said opposite end sendinga high pressure internalswabbing fluid blast into said one end for blowing the interior of the article clear of excess galvanizing metal to discharge through said opposite end of the article, whereby said external blowing at said opposite end prevents excess molten metal forcibly ejected by-the internal blast from the interior of the article from whipping around onto the external surface of said opposite end of the article.

8. In apparatus for removing excess molten galvanizing metal from tubular freshly internally and externally galvanized conduit, means for advancing the freshly galvanized conduit from the galvanizing tank through a linear path, means interposed stationarily in the path of movement of the conduit and arranged to blow an annular swabbing stream of fluid against the external surface of the conduit and angularly toward the trailing end of the conduit, and means engaging the advancing end of the conduit and halting the advance of the conduit while the external swabbing means is in such relation to the trailing end of the conduit that the swabbing fluid therefrom operates uninterruptedly on the trailing end portion of the conduit, said advancing end engaging means including an internal swabbing fluid discharge opening directed into the advancing end of the conduit to discharge a high pressure swabbing fluid blast into the conduit to travel through the conduit and discharge from said trailing end while the external swabbing fluid continues swabbing action on the trailing end to prevent excess molten metal which is forcibly ejected by the internal swabbing blast from whip-ping around onto the external surface of the trailing end of the conduit.

9. In apparatus for removing excess molten galvanizing metal from the interior of a freshly galvanized conduit, means for advancing a freshly galvanized conduit in a linear path, a blow tube positioned at the end of said linear path and having a conduit engaging and supporting mouth directed to engage the leading end of the conduit, means operative when the leading end of the conduit is engaged in said mouth to drive a blast of internal swabbing fluid under high pressure into the leading end of the conduit to travel through the conduit and discharge from the trailing end of the conduit, means for moving the blow tube away from the leading end of the internally swabbed conduit to separate the tube from the conduit following internal swabbing of the conduit, and means operatively controlled by the conduit for controlling operations of said blast driving means and said blow tube moving means.

10. In combination in apparatus for removing excess molten galvanizing material from freshly galvanized conduit, a spatter chamber having an entry opening at one side and an exit opening at the other side generally alined with the entry opening, a plurality of overhead magnetic conveyor rolls at said one side of the chamber and arranged to carry a freshly galvanized conduit section through said entry opening and advance the same through the chamber and through said exit opening, another set of conveyor rolls at said opposite side of the spatter chamber for engaging and advancing the conduit from said spatter chamber, an external swab located just outside of said exit opening and directing a stream of external swabbing fluid against the conduit to swab excess molten galvanizing metal from the exterior of the conduit into the spatter chamber, means interposed in the path of movement of the conduit section to engage the advancing end of the conduit section when the trailing end of the conduit section has almost reached said exit opening to halt the advance of the conduit section and drive a blast of high pressureinternal swabbing fluid through the conduit section to be ejected forcibly from the trailing end of the conduit section into the spatter chamber, and a flexible splatter-blocking plate attached at one'edge within the chamber adjacent to said opposite side of the chamber and having operating means adjacent its opposite edge, said operating means being operable when the trailing end of the conduit section has cleared the same to flex the plate into position between the trailing end of the conduit section and said entry opening to receive splatter from the trailing end of the conduit section, said actuating means being operable thereafter to flex the plate to the initial position thereof to clear the path between said openings for movement through the splatter chamber of a succeeding conduit section.

11. In combination in apparatus for removing excess galvanizing material from freshly galvanized conduit, a blow tube having a mouth constructed to receive the end of a freshly galvanized conduit therein, means for supplying the blow tube with a charge of high pressure internal swabbing fluid to discharge from said mouth into the freshly galvanized conduit therein, and means including a pair of pinch rolls for supporting the conduit with its end in said blow tube, said pinch rolls havng driving means acting on the pinch rolls to urge the same to maintain the conduit under endwise pressure into the blow tube month while the pinch rolls remain stationary with the conduit being swabbed.

12. In combination in apparatus for removing excess galvanizing material from freshly galvanized conduit, a blow tube having a mouth constructed to receive the end of a freshly galvanized conduit therein, means for supplying the blow tube with a charge of high pressure internal swabbing fluid to discharge from said mouth into the freshly galvanized conduit therein, and means including a pair of pinch rolls for supporting the conduit with its end in said blow tube, said pinch rolls having driving means acting on the pinch rolls to urge the same to maintain the conduit under endwise pressure into the blow tube mouth while the pinch rolls remain stationary with the conduit being swabbed, said driving means including a slip clutch which enables the pinch rolls to remain in said stationary relationship while the drive means continues to operate.

13. In combination in apparatus for cleaning excess galvanizing metal from freshly galvanized conduit sections, a conveyor for moving each freshly galvanized conduit section in a linear path, a blow tube operable when the conduit section has reached a certain position upon the conveyor to engage the leading end of the conduit section and blow a swabbing blast of fluid through the interior of the conduit section, and means controlled by the conduit section itself for moving the blow tube into and out of conduit section engaging position.

14. In apparatus for removing excess galvanizing metal from the interior of tubular freshly galvanized conduits, a blow tube for blowing a swabbing blast of superheated steam into the respective ends of conduits brought into position relative to the blow tube, means for supplying superheated steam to the blow tube, means for controlling the delivery of superheated steam to the blow tube by shots including a gate valve 15 having one end of an elongated operating stem thereon and projecting to a substantial distance therefrom, an intermittently operable device on the opposite end of the stem for reciprocating the stem and thereby opening and closing the valve, a heat dissipator about said operating stem, and. means operating in synchronism with move ment of the conduits for efiecting operation of said device.

WILLIAM S. PEARSON.

REFERENCES CITED The following references are of record in the file of this patent:

Number 16 UNITED STATES PATENTS Name Date Greenfield 1 Jan. 12, 1915 Barord Sept. 27, 1927 Barord Sept. 4, 1928 Moon Apr. '1, 1931 Moon May 2, 1933 Bedeil July 11, 1933 Uecker July 28, 1936 Reeveley Aug. 31, 1943 Stromquist May 24, 1949 

7. IN A METHOD OF REMOVING EXCESS MOLTEN GALVANIZING METAL FROM TUBULAR FRESHLY INTERNALLY AND EXTERNALLY GALVANIZED ARTICLES, THE STEPS OF BLOWING THE EXCESS MOLTEN GALVANIZING MATERIAL FROM THE EXTERNAL SURFACE OF THE ARTICLE PROGRESSIVELY FROM ONE END TO THE OPPOSITE END OF THE ARTICLE, AND WHILE UNINTERRUPTEDLY CONTINUING THE EXTERNAL BLOWING AT SAID OPPOSITE END SENDING A HIGH PRESSURE INTERNAL SWABBING FLUID BLAST INTO SAID ONE END FOR BLOWING THE INTERIOR OF THE ARTICLE 